Tesla Model 3 Aftermarket Stereo Installation : teslamotors The real breakdown of the electrical system and connections that will let you install anything you want on your own terms. The only real difference vs a normal car is that Tesla puts itself and the 12v battery to sleep. When it comes on it will blast the after market system with juice, providing electrical warnings and keeping you from driving. The solution was to put in a relay that slowly charges the after market equipment when the car awakes. Other things to note is that the audio is incredibly clean, but the low end is flat which is bad as it does not respect the loudness curve: Equal-loudness contour - Wikipedia. Simply put, humans cant percieve low end bass well so the speakers need to be louder to compensate (basically needing to create SPL to hit the line in that chart to feel the same loudness as everything else) . This is likely why bass heads thinks the subwoofer doesnt actually do anything. It produces sound but it's incredibly quiet. This is also why you dont build bass enclosures that have a flat response curve.